In article ,
"Edward Hennessey" wrote:

Glass works better than microballoons as a thickening agent but
because of the amount of
material necessary to keep the liquid from creeping off the rock, the
viscosity of the mix
prevents bubbles from easily migrating out.

A vaccuum pump and chamber recently arrived and next time out, they
will get a
trial. But other approaches and thoughts are always welcome.

Spread it out as thin as possible in your vacuum chamber (ie, a bunch of
petri dishes would be much better than a beaker, say) and give it some
time under vacuum. My personal analysis of the best way to do this has
always proved more complex to implement than has been worth it anywhere
I've needed to do this - that would be to pour the epoxy from one
container to another (or directly into the mold in the case of molded
parts) while under vacuum, and thus gets into mechanical seals and or
electrical apparatus to facilitate pouring while under vacuum. Can be
done, just more money and bother than has been desired to expend on this
detail.

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Cats, coffee, chocolate...vices to live by